This extra firm mattress is topped with NZ wool that adapts to keep you cool in summer and warm in winter. This foam-encased pocket spring mattress contains individual responsive springs, all housed in separate fabric pockets. Each spring absorbs and spreads weight across the bed to give you support and pressure relief for a comfortable night's sleep. The springs work independently to minimise partner disturbance and roll together. The foam edge support eliminates that feeling of rolling off the mattress's edge, which means you can sleep right to the edge of your bed.